A NOS 192/24 DAC with the PCM1794 (and WaveIO USB input)

First things first. The psu was the first thing I tackled. And before I went on to the other boards first a quick check. Yes! It all worked first time.=
 

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Great! and thanks, more to follow I hope :)
this grounding of the negative is intriguing...
I will run some AP test over that and post back if it does any measurable thing as well, which might give a clue why it sounds better? Ian, how would you describe it?

Grounding of the Negative seems to add more weight/scale to the sound is the best way I can describe it. I don't have any scope equipment here to take any measurements but it definitely sounds better in my system and to my ears.

I look forward to seeing the results of this change tested on a scope when you have time Doede.
 
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Hi Bas,

Thanks for the clarification.

Another tweak ( read in the Musical Fidelity upgrade description in their website) is wrapping a band of copper around the power supply capacitor- apparently it suppresses resonances.

I tried it using copper tape on the power supply cap of my Revox B77 reel deck. I have a feeling it may have improved things (I suspect a bit of belief is required). Any way, the good part is that it is easily reversible.

Cheers!

Ravi

PS: Awating delivery of my order sent by Doede. I will be able to report back when I assemble the DAC.
 
I tried it using copper tape on the power supply cap of my Revox B77 reel deck.
I've had copper around my psu polyprop caps. With one end soldered to ground. Just for kicks as well. Should act as a shield. Anyway. The amp I did that with was dead quiet.

PS: Awating delivery of my order sent by Doede. I will be able to report back when I assemble the DAC.
Did you also order the psu for the WaveIO. That really improves things. Or at least power it seperately with your own psu.
 
The package came yesterday and hope to start assembling soon.
Good luck.

I just ordered the 12v psu as well. Because yesterday I changed the 12v psu from the rakk dac mk 1 psu to the rakk dac mk 2 deluxe psu. The mk1 only supplied something like 170mA and has minimal filtering (Something Dave Davenport later fixed in his mk2) since more filtering gave the sound more body. Anyway to make a long story short. The improvement from mk1 psu to mk2 psu was nothing short of stunning. Suddenly I had George Benson in my room ;).
So now I want to try Doede's psu. And return the mk2 psu to its rightful owner the RAKK DAC MK 2. So I can use that in my other system.

Cheers,
Bas
 
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Balanced Output Options

Hi All,
after following this thread I've taken the decision to order a kit. It is on its way and initilaly I will build it as is with the single ended outputs. Can anyone recommend an add on board or circuit that would provide balanced outputs though please.
Regards
 
Hi Doede,
I have read your explenation on your site, and make mine decision to make one.
Words are words, but still there is something , I think your design is right.
Mine knowwlegde is not sufficient to design the delay in the I2S line.
So, I have order a waveIO board, and collecting / buy parts.
Still a few questions, I can't determine what is the L or R channel, i have read the
blue line in the delay circuit. and,
you use a output trafo, are you still use the A B iv resistors on that position, or
a ristor on the sec side?
I have good experiens with an outputtrafo.
Regards,
Zjaakco